Abstract
Purpose: :
Infrared (IR) imaging has been said to have advantages over fundoscopy in identifying subretinal structures –e.g. differentiaing choroidal naevi from non–pigmented lesions like haemorrhages. In this study we analysed near IR–reflectance images of choroidal naevi.
Methods: :
Patients with choroidal naevi were included. Near IR–reflectance, blue light autofluorescence and red–free imaging was carried out with a scanning laser ophthalmoscope (HRA classic), OCT images including infrared camera imaging were performed with a Zeiss Stratus OCT system.
Results: :
Six patients were analyzed. In red free and blue light autofluorescence imaging the naevi were not detectable. Using the IR–fundus camera of the OCT all naevi could be identified as dark lesions. By contrast, near IR–reflectance imaging revealed that some naevi were hyperreflectant while other were isoreflectant. One eye exhibited three neighbouring naevi which looked identical on fundoscopy with two being strongly IR–reflectant while the third was not. OCT imaging indicated that less IR–reflectant naevi are more heterogenous in density.
Conclusions: :
IR–imaging with a scanning laser ophthalmoscope is an easy to use technique which allows differentiation between types of choroidal naevus which clinically appear identical. Follow up studies might identify the value of IR–imaging in predicting the risk of malignant transformation.
Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • choroid • retina